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Have a 3.0 L H6 Outback VDC 2003 in excellent condition, mileage 105,466. I like to do maintenance before something becomes a real problem. During a routine oil change at a lube place, spotted the following:

1. A very tiny leak around a Valve Gasket – nothing significant, just saw a little wear on the edges of the gasket, and saw a small drop of oil under it – very very small and very very slow leak (have checked the floor of my garage every day).

2. Saw a bit of dry coolant crystals near one of the Head Gaskets, just a bit (I know when a Head Gasket is blown, you see a lot of coolant, and the coolant in the coolant reservoir gets very dirty)

3. A hole in the hose coming from the coolant reservoir above the reservoir (this hose obviously needs replacing though it only comes into play when extra coolant needed is drawn from the reservoir).

4.The coolant in the coolant reservoir was a bit dirty (not very dirty)
Which of the above need attention, and what would you suggest checking/doing?

Which of the above need attention, and what would you suggest checking/doing?

Not sure what you mean here. You already know they need attention, if you are asking if these are major problems and what order - I would say they are probably not severe, but prob would do the coolant first. Not sure if HGs are an issue on the H6. Coolant doesnt usually get "dirty" so that would worry me a little... do you mean it is discolored, etc? It might very well be original. Not sure if you need conditioner in it for the H6. If you are thinking these issues may be indicators of a bigger problem, get a hydrocarbon test done on the coolant. valve cover leak is nothing fix it if the oil bothers you or wait until it gets worse.

1. Wouldn't worry about it a whole lot, esp for a single drop of oil. Makeup oil is cheaper. There are some writeups around about doing the valve cover gaskets on the H6 though.

2. Would probably just keep an eye on it.

3. THIS IS PRIORITY 1 in my opinion. When the engine is cold, and the radiator cap is removed, is the radiator full right to the top? If not this hose needs replacing pronto. Some amount of coolant comes out when the engine is warm and is supposed to be drawn back in when it cools. But with that hole it is just going to draw in air.

seeping valve cover gaskets are no big deal - do them at the same time as the next spark plug change or if they leak too much oil - you start loosing a half a quart to a quart between oil changes or it starts to annoy you by hitting the exhaust and burning off or leaving spots in your driveway/garage.

headgaskets - that's a huge job, hope it doesn't start leaking significantly. monitor oil and coolant levels, sounds like it's a very tiny amount and nothing to worry about. i've often wondered if i saw this on an H6 if i would put some of the coolant conditioner that subaru requires for the H4 in it...i think i probably would on my own vehicle as i really don't want to get into an H6 headgasket if i have too. two of my daily drivers have this motor.

dirty overflow bottle means nothing, lots of older subarus get dirty reservoirs just based on time and use.

Yah I get dirty overflow on all my soobs too. There was a TSB or similar document out that it could cause a problem on some soobs, the crud getting sucked in the overflow getting stuck and blocking radiator cap proper operation. Their solution was to cut the bottom of the overflow hose at a 45 degree angle so it wasn't sitting right at the bottom of the tank. On mine, I just pull the hose up 1/2" or so so that it isn't sucking right from the bottom of the muck.

1. Wouldn't worry about it a whole lot, esp for a single drop of oil. Makeup oil is cheaper. There are some writeups around about doing the valve cover gaskets on the H6 though.

2. Would probably just keep an eye on it.

3. THIS IS PRIORITY 1 in my opinion. When the engine is cold, and the radiator cap is removed, is the radiator full right to the top? If not this hose needs replacing pronto. Some amount of coolant comes out when the engine is warm and is supposed to be drawn back in when it cools. But with that hole it is just going to draw in air.

While I haven't seen any issues with engine overheating yet, that explains why we would sometimes here some slight bubbling noises after parking after a drive, especially a highway drive. Do you think I should flush and replace the coolant when changing the hose?

seeping valve cover gaskets are no big deal - do them at the same time as the next spark plug change or if they leak too much oil - you start loosing a half a quart to a quart between oil changes or it starts to annoy you by hitting the exhaust and burning off or leaving spots in your driveway/garage.

headgaskets - that's a huge job, hope it doesn't start leaking significantly. monitor oil and coolant levels, sounds like it's a very tiny amount and nothing to worry about. i've often wondered if i saw this on an H6 if i would put some of the coolant conditioner that subaru requires for the H4 in it...i think i probably would on my own vehicle as i really don't want to get into an H6 headgasket if i have too. two of my daily drivers have this motor.

dirty overflow bottle means nothing, lots of older subarus get dirty reservoirs just based on time and use.

The seep looks too small to be of any worry - was just checking.

It's only a bit of coolant crystal that I saw under one of the head gaskets - probably not of consequence. Why do you think it would be helpful to add the H4 coolant conditioner? I'll ask our mechanic what he thinks - super knowledgeable and straight shooter.

Yah I get dirty overflow on all my soobs too. There was a TSB or similar document out that it could cause a problem on some soobs, the crud getting sucked in the overflow getting stuck and blocking radiator cap proper operation. Their solution was to cut the bottom of the overflow hose at a 45 degree angle so it wasn't sitting right at the bottom of the tank. On mine, I just pull the hose up 1/2" or so so that it isn't sucking right from the bottom of the muck.

What does "TSB" stand for?

Probably a good idea to cut the coolant hose on a 45 degree angle AND pull it up.

But how do you keep the coolant hose up - with a plumbing clamp of some kind? (there's probably one there already I just can't remember without looking)

My overflow hoses seem to stay up about 3/8" or so just by lifting them, the friction seems to keep them there. Some electrical tape wrapped around it would keep it from going down in there.

Depends what you mean by coolant flush. Subaru doesn't want flushing machines to be used (except one certain type), because they might be contaminated with coolant and metals from other vehicles.

And on your other engine oil thread question...just don't forget you have an engine oil lubricated timing chain and tensioners. The timing belt engines you can get away with more with the oil, but some of the H6's already had issues with the timing chain tensioners....so good oil in the right weight changed in time is important.

You don't want her to overheat....ever. Often overheating will take out the water pump, and since yours is driven off the timing chain, that is a big job to get out those like 62 bolts in the timing chain cover.

So I shouldn't replace the coolant with fresh coolant? Going to indie garage so important I let them know what should be done. Do I have to go to the dealer for a lot more $ just to replace the coolant?

Going to pick up the Subaru OEM coolant additive ($2) which Subaru doesn't require but recommends for the H6 engines.

Is it due for a coolant change? If so or you don't know when it was done last, then it's probably not a bad idea.

Not recommended to use Dexcool or dexclones like Prestone in there. Make sure the place you take it knows how to get the air bubble out after refilling, or uses a vacuum filler. I use a vacuum filler on all my soobs. It is pretty slick, leaving basically no air in the system after its refilled, without needing to remove any rad hoses while filling or reving the engine with the cap off, etc.

Thanks Porcupine73. What type of coolant is recommended and would you know how much (I'll check my manual as well)? Does it come in a standard volume?

If I'm going to replace the coolant it will probably be cheaper for me to pick it up from Walmart or another discount store before I take it in to the indie garage.

The coolant should have been replaced at the 90K servicing, which was done by a Subaru dealer (we had a good deal and the car was still under a Gold Plus coverage program at the time).

A Subaru owner I met at the Subaru dealer parts department where I picked up Black OEM oil filters and coolant conditioner warned against using a power flushing system which could push bits of metal and gunk into the engine. Is this vacuum device anything like that?

For 3.0 Liter engines, the Subaru manual recommends 8.4 US qt (7.9L or 7.0 Imp qt) and recommends using either Subaru genuine (of course) or an equivalent: a mixture of 50% soft water and 50% ethylene-glycol basis coolant.

Sometimes the value they list in the owners manual is for a complete drain, i.e. removing the block drains or changing the water pump. Sometimes you will get a bit less out just the radiator drain.

Right, do not use a flush machine, except there was one Subaru said is OK; I mentioned that in a previous post too: "Depends what you mean by coolant flush. Subaru doesn't want flushing machines to be used (except one certain type), because they might be contaminated with coolant and metals from other vehicles."

If you want to be plenty conservative, then just get the Subaru coolant for it. But get the old green, not the new blue 'super coolant'.

Any water added should be distilled or R/O. 'Soft' usually just means deionized (i.e. water softener). It just shouldn't be tap water normally (unless you have a water softener). It's funny how Subaru says that yet this one time they had to issue a TSB for coolant replacement in new soobs because there was too much chlorine in the coolant. whoops!

Have a 3.0 L H6 Outback VDC 2003 in excellent condition, mileage 105,466. I like to do maintenance before something becomes a real problem. During a routine oil change at a lube place, spotted the following:

1. A very tiny leak around a Valve Gasket – nothing significant, just saw a little wear on the edges of the gasket, and saw a small drop of oil under it – very very small and very very slow leak (have checked the floor of my garage every day).

2. Saw a bit of dry coolant crystals near one of the Head Gaskets, just a bit (I know when a Head Gasket is blown, you see a lot of coolant, and the coolant in the coolant reservoir gets very dirty)

3. A hole in the hose coming from the coolant reservoir above the reservoir (this hose obviously needs replacing though it only comes into play when extra coolant needed is drawn from the reservoir).

4.The coolant in the coolant reservoir was a bit dirty (not very dirty)Which of the above need attention, and what would you suggest checking/doing?

I have a bigger case of #1, engine is wet but no drips in the driveway.

I also have one head gasket that looks like it has had a wash in penn-central green paint, have never seen it wet, at 170K I'm just closing my eyes and ignoring it.

Sometimes the value they list in the owners manual is for a complete drain, i.e. removing the block drains or changing the water pump. Sometimes you will get a bit less out just the radiator drain.

Right, do not use a flush machine, except there was one Subaru said is OK; I mentioned that in a previous post too: "Depends what you mean by coolant flush. Subaru doesn't want flushing machines to be used (except one certain type), because they might be contaminated with coolant and metals from other vehicles."

If you want to be plenty conservative, then just get the Subaru coolant for it. But get the old green, not the new blue 'super coolant'.

Any water added should be distilled or R/O. 'Soft' usually just means deionized (i.e. water softener). It just shouldn't be tap water normally (unless you have a water softener). It's funny how Subaru says that yet this one time they had to issue a TSB for coolant replacement in new soobs because there was too much chlorine in the coolant. whoops!

Is coolant sold in one size that will suffice for what I'll need? Sorry for the question but I've never had to buy it myself before.

Vacuum draining machines are ok though?

When I asked the Subaru parts dealer which coolant they had, they described it as the "blue green stuff." Very helpful LOL. Which do you mean by the old green? And if I buy from Walmart or an auto parts store, which coolant to get?

Our tap water comes from the Hetch Hetchy Reservoir in Yosemite and is 8.4-8.6 pH and 0 ppm dissolved solids - don't think you can get softer than that. We have an R/O filter as well, though with water this soft out of the tap, is R/O necessary?

Is coolant sold in one size that will suffice for what I'll need? Sorry for the question but I've never had to buy it myself before.

Vacuum draining machines are ok though?

When I asked the Subaru parts dealer which coolant they had, they described it as the "blue green stuff." Very helpful LOL. Which do you mean by the old green? And if I buy from Walmart or an auto parts store, which coolant to get?

Our tap water comes from the Hetch Hetchy Reservoir in Yosemite and is 8.4-8.6 pH and 0 ppm dissolved solids - don't think you can get softer than that. We have an R/O filter as well, though with water this soft out of the tap, is R/O necessary?

The coolant is normally sold by the gallon, but I've seen some dealers price it by the quart. I can't remember if it is premixed, I don't think so.

The vacuum is not for draining - it is for the refilling. It evacuates basically all air from the cooling system, then lets the coolant get sucked in. This method is fine. The flushing machines are a problem because they can recirculate traces of old coolant from other vehicles, which may be contaminated with various cooling system metals not present in Subaru, and traces of incompatible coolants.

I would still go with the R/O even if you have 'soft' tap water. Why not, you need what, a gallon or so of it at the most?

For 3.0 Liter engines, the Subaru manual recommends 8.4 US qt (7.9L or 7.0 Imp qt) and recommends using either Subaru genuine (of course) or an equivalent: a mixture of 50% soft water and 50% ethylene-glycol basis coolant.

Which non-OEM ethylene-glycol basis coolant do you recommend? Likely much cheaper at Walmart or other store than buying OEM from dealer, and in this case OEM likely makes no difference.

I'll use R/O water as we have an R/O filter.

Just realized - I have no idea if the Subaru dealer who did our 90K servicing (we're at 105K now) already added Subaru OEM coolant conditioner to the coolant, which they likely replaced at that service. If I don't replace the coolant now, I would be adding a second helping - anyone know if that's safe?